Submission #1200568

#	Time	Username	Problem	Language	Result	Execution time	Memory
1200568		countless	Rainforest Jumps (APIO21_jumps)	C++20	8 / 100	4093 ms	18476 KiB

jumps

#include "jumps.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;

const ll MOD = 998244353;
const ll INF = 1e18;
const ld EPS = 1e-12;

#define endl "\n"
#define sp <<" "<<
#define REP(i, a, b) for(ll i = a; i < b; i++)
#define dbg(x) cout << #x << " = " << x << endl
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fast_io() ios_base::sync_with_stdio(false); cin.tie(NULL)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

template <typename Key, typename Value>
using hash_map = unordered_map<Key, Value, custom_hash>;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// uniform_int_distribution<int>(a, b)(rng);
// shuffle(all(a), rng);

int n, timer = 0;
vector<int> h;
vector<vector<int>> adj;

// n, q: 7 3
// h:    3 2 1 6 4 5 7
//
// 4 4 6 6
// 1 3 5 6
// 0 1 2 2

void init(int N, vector<int> H) {
    n = N;
    h = H;
    adj.resize(n);

    // build DAG
    set<int> s;
    REP(i, 0, n) s.insert(i);

    vector<pair<int, int>> ord(n);
    REP(i, 0, n) { ord[i] = {h[i], i}; }
    sort(all(ord));
    
    REP(i, 0, n) {
        auto [val, ind] = ord[i];

        auto left = s.lower_bound(ind);
        auto right = s.upper_bound(ind);

        if (left != s.begin()) {
            left = prev(left);
            adj[ind].push_back(*left);
            // adj[*left].push_back(ind);
        }

        if (right != s.end()) {
            adj[ind].push_back(*right);
            // adj[*right].push_back(ind);
        }

        s.erase(s.find(ind));
    }

    // topo sort
    // vector<bool> vis(n, false);
    // vector<int> topsort;
    // auto dfs = [&](auto &&dfs, int u) -> void {
    //     vis[u] = true;
    //     for (auto &v : adj[u]) {
    //         if (!vis[v]) {
    //             dfs(dfs, v);
    //         }
    //     }

    //     topsort.push_back(u);
    // };

    // REP(i, 0, n) {
    //     if (!vis[i]) {
    //         dfs(dfs, i);
    //     }
    // }
}

int minimum_jumps(int A, int B, int C, int D) {
    int ans = INT_MAX;

    auto bfs = [&](auto &&bfs, int u) -> void {
        vector<bool> vis(n, false);
        queue<pair<int, int>> q;
        q.push({u, 1});

        while (!q.empty()) {
            auto [v, d] = q.front(); q.pop();

            for (auto &w : adj[v]) {
                if (!vis[w]) {
                    if (C <= w and w <= D) {
                        ans = min(ans, d);
                        return;
                    }

                    q.push({w, d + 1});
                    vis[w] = true;
                }
            }
        }
    };

    for (int i = A; i <= B; i++) {
        bfs(bfs, i);
    }

    if (ans == INT_MAX) {
        ans = -1;
    }

    return ans;
}

• Subtask 1: 0 / 4
• Subtask 2: 8 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 12
• Subtask 5: 0 / 23
• Subtask 6: 0 / 21
• Subtask 7: 0 / 19